1. Don't shoot your M4 when it's really cold outside. It'll break. Likewise...if it's been in your trunk for a while and is really cold...let it warm up before shooting it. Search "Cold" and you'll get "Broken V2 mechbox" (not litterally...but that's the Cole's notes)

2. What you're looking at is the dust cover of the ejection port. Right side of the rifle, above the magwell, in the upper receiver.

3. When you pull back the charging handle, the dust cover should flip open. Some don't and you have to open it with your finger nail. A fake metal sheet may be in there...it should slide back, but if it doesn't just push it back gently.

4. Inside near the front, you'll see the right side of the hopup unit.

5. The rear-most dial (and usually the biggest one) is the hopup adjustment wheel. That gear turns other gears that affect how much hopup you have on.

6. Looking at the hopup adjustment wheel. You turn it clockwise for more hopup and counter clockwise for less. The optimal amount will cause your shots to go straight out and then drop. Start with the hopup off...and add a bit little by little.

7. It's FREAKING FREEZING outside...so your hopup rubber has probably stiffened up... When it does that, it will cease to put any backspin on the bbs...causing lousy shots. Too much oil, water, etc...on the rubber will do the same thing.